Artificial structures visible from space

Artificial structures visible from space without magnification include highways, dams, and cities.[1][2]

Whether an object is visible depends significantly on the height above sea level from where it is observed. The Kármán line, at 100 kilometres (62 mi), is accepted by the World Air Sports Federation, an international standard-setting and record-keeping body for aeronautics and astronautics, as the boundary between the Earth's atmosphere and outer space.[3] However, astronauts typically orbit the Earth at several hundreds of kilometres;[4] the ISS, for example, orbits at about 420 km (260 mi) above the Earth,[5] and the Moon orbits at about 380,000 km (240,000 mi) away.[4]

  1. ^ Emery, David. "What's Visible from Outer Space". About.com: Urban legends. Archived from the original on 28 September 2009. Retrieved 12 May 2010.{{cite web}}: CS1 maint: unfit URL (link)
  2. ^ Cecil Adams. "Is the". The Straight Dope. Retrieved 12 May 2010.
  3. ^ "The 100 km Boundary for Astronautics" (DOC). Fédération Aéronautique Internationale Press Release. 24 June 2004. Retrieved 30 October 2006.
  4. ^ a b Mikkelson, David (November 11, 2001). "Is the Great Wall of China Visible from the Moon?". Snopes. Retrieved 2010-05-12.
  5. ^ Peat, Chris. "ISS – Orbit". Heavens-Above. Retrieved 7 January 2020.